Method and apparatus for making paper



May 6, 1930.

.C. C. HOCKLEY METHOD AND APPARATUS FOR MAKING PAPER 2 Sheets-Sheet lOriginal Filed June 5, 1924 May 6, 1930.. c. c. HOCKLEY METHOD ANDAPPARATUS FOR MAKING PAPER v Original Filed June 5, 1924 2 Sheets-Sheet2 172276 CZZZ(73 (lfi oc/tZeg Patented May 6 1930 UNITED STATES PATENTOFFICE CLAUDE C. HOGKLEY, OF PORTLAND, OREGOll 7 METHOD AND APPARATUSFOR- MA KIN 'G PAPER Befile of application Serial No. 717,945, filed{Tune 5, 1924. This application filed June 26, 1928. Seria 5 ing of theweb, initspassage over said dryer I section thereby to increase thedaily production, and reduce the cost of manufacturing v the paper.

My present application is to'c omplete and more particularly describethe method and apparatus described in my application for Letters Patent,filed June 5, 1924, Serial No.

717,945, entitled Process of making paper.

In making'pap'er, as well-known, it is customary to form the web of thesheet on what is generally called the wet end of the paper machine, andthen remove the water, and finally drying the sheet by passing it overone or more steameheated drying rolls.

As the sheet of paper comes to the dryerrolls it has a relatively highmoisture content and therefore an eflicient method and apparatus fordrying the sheet is essential.

In the ordinary method of drying, the moisture in the sheet is drivenout by the heat of the. hot dryer-rolls, and is carried ofi by a naturaldraft, or chimney, which leads from the hood which covers the dryerrolls.

In this mode of procedure the drying of the paper web was to some extenthastened by passing over the dryer-roll a volume of moving, heated air,thereby to absorb and carry oi the vapors emitted by the web; but it wasthought that ample volume of air was suificient, and no attention wasgiven to its velocity, nor the angle at which the sheet of air impingedupon the web of paper.

Furthermore economy in use of heat and power must be taken intoconsideration; and to accomplish efiicient drying with saving of heatand power is the object of my invention.

' In brief I have discovered that the drying of the web of paper passingover a drying roll may be greatly promoted by impinging upon the web ofpaper carried by said roll, a relatively thin transverse sheet of airpreferably heated moving at high velocity, in the direction of motion ofsaid roll, with said sheet of air constrained to a plane, which ifproduced, would cut the circumferential surface of said roll and thencausing the flow of said air to continue over a substantial longitudinalperipheral section of said roll and finally releasing said air.

My experiments have demonstrated that it will not answer to direct thesheet of air in a plane which would be tan ent to that sec-- web ofpaper in such manner as to break up n the film of moisture immediatelyoverlying the web, which film if not broken up would tend to insulatethe web from the drying air and reduce the effectiveness of the latter.This will slow up materially the drying ef fect of said current of air;on the other hand by breaking up said insulating film of moisture thedrying eifect of said current of airis greatly promoted.

In order to carry my 1nvent1on into praotice, I found it convenient touse 1n combination with a drier roll, means for promotingthe drying ofthe web passed over the roll, comprising a hood open at one end and.ar-. ranged to inclose and form a low passageway over a circumferentialsection of substantial length of the drier roll, and means for blowing asheet of air into the other end of said hood at hi h velocity in thedirection of the rotation 0 said roll, and in a plane:

which if produced would cut the circumferential surface of said drierroll. Referring now to the accompanying drawings, illustrating myinvention and forming part of this specification:

Fig. 1 shows a diagrammatic end elevation of a dryer-roll of a papermaking machine embodying my invention; Fig. 2 shows a side elevation ofthe same; Fig. 3 shows a longitudinal sectional detail of thepressurebox and hood covering a circumferential segment of the dryer-roll and bywhich air is impinged at high'velocity on the dryer-roll and furtherillustrates means for adjusting the orifices of the airejecting nozzlesdischarging from the pressure box;

Fig. 4 shows a section taken on the line 4-4 of Fig. 3, and illustratesthe manner in which the movable members of said air nozzles areadjustably carried on a pipe or shaft, which is journaled in the ends ofthe housing of the pressure box; and

Fig. 5 illustrates other means for adjusting the said air-ejectingorifices.

' In the drawings, a designates the outer I casing,'or hood; (1indicates the main shaft which is suitably mounted, and which carriesthe dr or roll a, and a is the exhaust by which t e air current isremoved after it haspassed under the hood and taken up the moisture,from the section of the paper sheet a carriedby the dryer roll. Thearrows in Fig. 1 indicate the direction of travel of the sheet beingdried; the entry point of the sheet in the drying apparatus being at aand the exit point at a respectively.

' As shown in Fig. 1, two segments of the dryer roll are provided withmy drying meansone on the right the other on the left-the plarts ofwhich means are designatedby t e same reference characters.

6 is the inlet ipe leading from 'a source of air supply un or pressure,and preferably preheated in anyconvenient way; and b is what is known asthe pressure box. From this pressure box the air is projectedtangentially against thewet paper sheet by the nozzles 6 under the hood0 as shown in Fig. 3.

Q Each nozzle 7) is constructed to permit the adjustment of its airprojecting orifice; and

I prefer to employ, a single nozzle extended across the entire face ofthe dryer-roll. In-

stead of such single nozzle a suitable closely arranged series ofseparate nozzles may be provided, but I have not found such anarrangement to work out as well in practical results as by theemployment of a single slit type of nozzle. I prefer to use two suchlong narrow nozzle orifices in the pressure gox, gne above the other asillustrated in The hood a is so arranged with respect to the underlyingcircumferential segment of the dryer roll as to provide a low passagewaythereover, in order that only a relatively thin stratum of air at highvelocity will be moved over the paper web under the hood and furtherwill be held in close contact with the circumference of the dryer roll.

The high velocity of the air thus driven through the hood (1 functionsto breakup the film of moisture-saturated air that otherwise-. wouldtend to form a shield over the paper web and reduce materially the speedof its drying.

The air projected by the nozzles is prefer- I ably preheated, and blower(not shown) is used to drive the air through the pressure box at highvelocity. And the air nozzles I) must be so arranged as to impinge uponthe sheet of air upon the web carried by the drier roll,.in a planewhich if produced would cut the circumferential surface of the dryerrollsince such accelerates the absorption and effects the rapid removal ofthe V3.1 pors carried and emitted by the web of paper.

The nozzles 15 are preferably so arranged as to provide a narrow orificeor slit extending across the entire face of the dryer rolls, as alreadymentioned. The construction is preferably such, also, that adjustmentcan be made of the orifice from the exterior of the pressure box. Mypreferred arrangement for this purpose is shown in Fig. 3 and Fig. 4.The lower; part of the nozzle consists of a metal platec', set at asuitable angle and 1 extending the width of the dryer roll as shown, andpermanently secured in place. The upper companion nozzle plate (1 is,however, adapted to-be moved with respect to the lower plate, to varythe opening between the two. As shown by Fig. 4 the upper nozzle plate(1 is carried by a series of spiders I), mounted on a common shaft b",journaled in bearings located in the side walls of the pressure box I),with one end of the shaft extending through the side wall; and on suchprojecting end of the shaft may be provided a wheel" 6, or othersuitable controlling means, to facilitate the desired adjustment of theorifices of the nozzles. Set screws e permit the adjustment of saidspiders b on the shaft 6 as desired.

In Fig. 5 a modified form of nozzle arrangement is shown.' The upperplate of the nozzle 6 is integral with the bottom of the pressure box,and the lower nozzle plate I) is adapted to be moved and adjusted withrespect to the upper plate; the plate I) being carried on a movablesupporting bracket secured in place by a bolt 6".

By the employment of my method and apparatus the moisture of the papermay be removed very rapidly, thus reducing the amount of steam used indrying, increasing the productlon; and, in consequence, reducother endof said hood at high velocity upon the web, in a plane which if producedwould cut the circumferential surface of said er roll whereby to breakup the film of ins ating moisture envelogifig the web of paper.

2. In a paper ma g machine, the combination with a dryer roll of meansfor promoting the drying of the web of paper passed over said roll,comprising a hood open at one end and arranged to enclose and or'ma lowpassageway over a circumferential section of said roll, and meansincludin a pressure box provided with a series 0 nozzles adapted forblowing a transverse sheet of air into the other end of said hood athigh velocity upon the web, in a plane which if produced would cut thecircumferential surface of said dryer roll, whereby to'break up the filmof insulating moisture enveloping the web of paper;

3. In a paper making machine, the combination with adryer roll of meansfor promoting the drying of the web of paper passed over said roll,comprising a hood open at one end and arranged to enclose and form a lowpassageway over a circumferential section of said roll, and meansincluding an adjustable nozzle connected to a source of air underpressure for blowing a sheet of air into the other end of said hood at.highvelocity upon the web, in a plane which if produced would cut thecircumferentialsurface of said dryer roll, whereby to break up the filmof insulating moisture enveloping the web of paper. 4. In a paper makingmachine, the combination with a dryer roll of means for promoting thedrying ofthe web of paper passed over said roll, comprisin a hood openat one end and arranged to inc ose and form a low passageway over acircumferential section of said roll, and means including a nozzle forblowing a transverse sheet of reheated air into the other end of saidood at high velocity upon the .web in a plane which if produced wouldcut the circumferential surface of said er roll, whereby to break up thefilm of ins ating moisture enveloping the 'web of paper.

a I CLAUDE Q'HOCKLEY.

